A computer virus dubbed the world's "first cyber superweapon" by experts and which may have been designed to attack Iran's nuclear facilities has found a new target -- China.

The Stuxnet computer worm has wreaked havoc in China, infecting millions of computers around the country, state media reported this week.

Stuxnet is feared by experts around the globe as it can break into computers that control machinery at the heart of industry, allowing an attacker to assume control of critical systems like pumps, motors, alarms and valves.

It could, technically, make factory boilers explode, destroy gas pipelines or even cause a nuclear plant to malfunction.

The virus targets control systems made by German industrial giant Siemens commonly used to manage water supplies, oil rigs, power plants and other industrial facilities.